For the first time, the amount of digital information generated about people surpasses the amount they create themselves, says an IDC report commissioned by storage firm EMC.
This "digital shadow" is created by an ever growing digital universe, fed from the explosion in use of digital cameras, digital TVs, surveillance cameras and social networks.
IDC's white paper, called The Diverse and Exploding Digital Universe: An Updated Forecast of Worldwide Information Growth Through 2011, is an update on last year's report.
At 281 billion gigabytes (281 exabytes), the digital universe in 2007 was 10% bigger than previously estimated, said the latest report.
And with a compound annual growth rate of almost 60%, the digital universe is growing faster and projected to reach 1.8 zettabytes (1,800 exabytes) in 2011, a 10-fold increase over five years.
The average person's digital shadow - all the digital information generated on them - now surpasses the amount of digital information they actively create themselves, said the report.
To calculate the size of your own digital footprint, download a copy of the personal digital footprint calculator.